免费在线工具

Send HTTP requests with custom methods, headers, and bodies, then inspect status, headers, and response — no CORS limits.

Minify SQL queries by removing extra whitespace and optional comments, with keyword casing controls.

Normality calculator free — convert N, molarity, and equivalents per mole. Find normality from mass and volume. Chemistry titration prep in your browser.

Calculate cell count after binary fission — solve for N, N₀, divisions, generation time, or elapsed time with step-by-step growth table. Free, browser-based.

Compute 2D and 3D vector operations — add, subtract, dot product, cross product, magnitude, unit vector, angle, and projection — with steps.

Calculate cosmological redshift from wavelengths or recession velocity. Convert z to velocity, Hubble distance, and scale factor. Free, browser-based astronomy tool.

Calculate ultimate and allowable soil bearing capacity using Terzaghi's equation for strip, square, and circular footings. Enter cohesion, friction angle φ, unit weight, depth, and footing width. Compare applied pressure to q_allow. Metric and imperial units. Free, browser-based.

Calculate fluid velocity from volumetric flow rate and cross-section geometry. Modes: circular pipe, rectangular channel, annulus, known area, continuity (pipe reducer), and velocity unit converter. Reynolds number and flow regime. Metric and imperial units. Free, browser-based.

Generate SEO-friendly blog posts with title, meta description, and markdown content using your own AI API key.

Visually build CSS gradients with a stop rail, color harmony, mesh layers, and copy-ready CSS variables.

Estimate YouTube ad revenue from views and RPM. See daily, monthly, and yearly earnings with monetized view rate adjustments.

Encode UTF-8 text to Base64 instantly in your browser with byte-size stats.